The Queen will say she draws strength from "ordinary people doing extraordinary things" in her annual televised Christmas Day address.
Volunteers, carers, community workers and good neighbours are unsung heroes whose quiet dedication makes them special, she will say.
She will also praise the achievements of the UK's Olympians and Paralympians.
The address was recorded before news broke that her granddaughter, Zara Tindall, had lost her baby.
The 10-minute message, filmed in Buckingham Palace's regency room, will be broadcast at 15:00 GMT on BBC1, ITV, Sky News channel and BBC Radio 4.
For the occasion, the Queen wore a deep jade, silk cloque dress by Angela Kelly, as well as a pearl and diamond brooch previously worn by the late Queen Mother.
In the speech, which will also be broadcast across the Commonwealth, the Queen will congratulate British Olympic and Paralympic athletes.
"Having discovered abilities they scarcely knew they had, these athletes are now inspiring others," she will say.
Team GB and Paralympics GB both came second in this year's Rio Games.
Her Majesty will also reflect on the achievements of the Duke of Edinburgh's Award, which celebrated its 60th anniversary this year, and The Prince's Trust, which was 40 years old in 2016.
Earlier this week, Buckingham Palace said the Queen would step down as patron of 25 charities and organisations, including the NSPCC, Battersea Dog's Home and Save the Children.
The Queen remains patron of some 600 charities and bodies, and will highlight their work in the Christmas address.
Zara Tindall, the equestrian champion, who is married to former England rugby player Mike Tindall, was due to give birth to her second child in the late spring.
The baby would have been the Queen and Duke of Edinburgh's sixth great-grandchild
Buckingham Palace said it would not comment on the private matter.
In this year's alternative Christmas message on Channel 4, Brendan Cox, the widower of murdered MP Jo Cox, will call for an end to the "rise of hatred" and pay tribute to his wife.
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